This invention relates to storage-stable, alkaline laundry detergent compositions, preferred embodiments of which exhibit excellent particulate and greasy/oily soil removal performance, as well as fabric softening, static control and dye transfer inhibition benefits, to fabrics laundered therewith.
It is taught in U.S. patent application Ser. No. 919,341, Cockrell, filed June 26, 1978, and U.S. patent application Ser. No. 919,181, Murphy, filed June 26, 1978, both of which are incorporated herein by reference, that by selection and combination of specific types of nonionic and cationic surfactants, excellent particulate and greasy/oily soil removal laundering performance can be obtained. In preferred embodiments of those compositions, by choosing specific types of cationic surface-active agents, biodegradable laundry detergent compositions can be formulated which exhibit particulate and grease/oil removal benefits as well as fabric softening, static control, and dye transfer inhibition benefits. Detergent compositions containing these specific biodegradable surfactants are described in U.S. patent application Ser. No. 919,343, Letton, filed June 26, 1978, and U.S. patent application Ser. No. 919,344, Letton, filed June 26, 1978, both of which are incorporated herein by reference.
It is further taught in the above applications that it is desirable that the detergent compositions form alkaline laundry solutions in order to improve the removal of oily body soils. However, because these preferred cationic surfactants contain a biodegradable linkage, such as an ester or amide linkage, they tend to hydrolyze upon storage and use, when included in such alkaline detergent compositions, thereby reducing their effectiveness during the laundering operation. It has now been found that by using the specific types of alkalinity sources defined herein, alkaline detergent compositions may be formulated which minimize the hydrolysis of hydrolyzable linkage-containing cationic surfactants, and particularly the preferred biodegradable cationic surfactants discussed above, during storage and use.
It is, therefore, an object of the present invention to provide alkaline laundry detergent compositions, containing cationic surfactants including hydrolyzable linkages, which are storage-stable.
It is a further object of the present invention to provide laundry detergent compositions which yield excellent removal of particulate and greasy/oily soils, as well as fabric softening, static control, and dye transfer inhibition, to fabrics laundered therewith.
It is a still further object of the present invention to provide laundry detergent compositions, yielding the above cleaning and fabric care benefits, which are biodegradable.
It is yet another object of the present invention to provide a process for laundering fabrics, yielding excellent removal of oily body soils, clay and greasy/oily soils, utilizing detergent compositions which contain selected cationic and nonionic surfactants.